


More than Kin

by cyphernaut



Series: Sick Day Universe [4]
Category: Sherlock (TV)
Genre: Age Play, Discipline, Spanking
Language: English
Status: Completed
Published: 2016-01-24
Updated: 2016-02-15
Packaged: 2018-05-15 20:52:24
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 7,871
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5799754
Author URL: https://archiveofourown.org/users/cyphernaut/pseuds/cyphernaut
Summary: <blockquote class="userstuff">
              <p>Little!Sherlock must come to terms with John's relationship with Mary.</p><p>The John/Mary is presumed, but not explicit, and the John/Sherlock and Mary/Sherlock refer to the ageplay relationships.</p><p>Spanking is kind of an exaggeration, but there's a smack in there, if that triggers you.</p><p>Set in the Sick Day universe.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> Thanks so much to embalmer56, who did so much more than beta this work. Thanks for the brainstorming, the troubleshooting, the moral support, and cheer leading. It wouldn't be written without you.

Sherlock sat in the midst of a heap of papers, scanning them for possible evidence of fraud as he kept his ears firmly focussed on the stairs that led to the flat. John had come through the main door several minutes ago, but had apparently stopped at Mrs. Hudson's for a chat. Or rather, John _and Mary_ had stopped there. Sherlock frowned.

When John's, and only John's, footsteps sounded from through the flat door, Sherlock perked up and shoved all the papers into a precarious pile. He left it leaning against the chair and ran to the door just as it opened and John walked through. 

“Look, I tidied up for you!”

“Yes, I see that,” John said, greeting him with a kiss and wiping a smudge of something from above Sherlock's eyebrow. “We'll still need to clear the table, though. Mary made bread rolls, and we picked up some takeaway lasagne. Mrs. Hudson has a salad she wants us to eat, too. Mary's getting it from her now.”

“I don't want any salad. Mary can stay downstairs with Mrs. Hudson.” He turned to assess the table, which had already been cleared off enough for two people to eat fairly comfortably.

“Come here, Sherlock.” Sherlock followed John to the sofa, where he was pulled down for a cuddle. He melted into it cautiously, knowing he would not want to hear what John had to say. “Mary is very much looking forward to seeing you.”

“I only want to see you, and not Mary,” he mumbled into John's shoulder.

John lifted Sherlock's chin back up so that they were looking into each other's eyes. “We talked about this. Mary and I are getting married, and I'd like my wife and my best friend to get along with one another.”

As Sherlock looked away in dissatisfaction, John used the opportunity to kiss the back of his head. Sherlock pressed the heels of his hands over his eyes, so immersed in his own resentment that he didn't notice Mary's approach until she appeared beside them, food in hand.

“Is everything all right?” she asked, setting the food on the coffee table in front of them.

Turning quickly, Sherlock clutched John before he could answer. “John is my best friend. Who's your best friend, Mary?”

“Certainly not John, as he appears to be taken in the best friend department.”

“Yeah, he is.” He buried his face in John's neck, breathing in his scent whilst trying to ignore the slight hint of Mary's perfume, or for that matter, any aspect of her presence. Despite his efforts, she lay a hand on his shoulder and a kiss on the top of his head.

“It's good to see you, Sherlock.”

Sherlock shrugged off her hand and kissed John's cheek, arms firmly wrapped around his head, effectively guarding him from any attempted affection on Mary's part. She allowed them the moment as she began to lay the table, moving Sherlock's things from it without any thought to the system he'd created. 

“You're messing up my evidence!” he shouted.

John's hand ran soothing circles on Sherlock's back, but Sherlock knew he'd earned a scolding. “Sherlock,” John warned him, even though Mary didn't seem to care she'd been shouted at.

“We'll put it back after we eat,” she reassured him.

Sherlock was careful not to raise his voice as he glared at her. “You don't know where anything goes.”

“You'll know where to put it,” John said sternly, and Sherlock baulked at the idea that he would have to arrange everything to his satisfaction again because of Mary's stupidity. He was weighing the consequences of saying as much when Mary spoke up.

“I remember where everything was, sweetie.”

“No, you don't! The average human memory-”

“Sherlock!” John's tone had gone considerably past warning, and his hands held Sherlock firmly in place.

“It's okay, John.” Mary began to lay the assortment of files, specimens, and scientific equipment on the floor. “See? It's the same.”

He inspected the display. In fact, it was exactly as he had placed it on the table earlier. He clung harder to John and tried not to strop as Mary set out the cutlery.

“Okay, love. It's time to eat,” John told him, trying to prise Sherlock's fingers from the fabric of his shirt.

“I'm not hungry,” he protested, just as John managed to free himself and walk toward the kitchen.

Mary, despite Sherlock's objections, set down a third plate before taking her own seat. “Oh, Sherlock, I have to eat with John every night. I need some new company.”

After John sat beside her, Sherlock rushed over, alarmed that they might eat without him. “I'll have some lasagne, but the bread rolls look revolting.”

* * *

After a dinner filled with tedious conversation and irritatingly delicious bread rolls, Sherlock was finally able to work on his research. Mary had offered to do the washing up so that he and John could spend some time together, the least she could do after ruining the meal with her attempts at drawing Sherlock into a conversation.

Sherlock ran through the case for John, pausing frequently to give him an opportunity to comment on Sherlock's brilliance. 

“Is this a case you're working on?” Mary asked.

Sherlock continued to peruse the photos, carefully blocking out any inane questions that might come his way.

“Mary asked you a question, love,” John prompted him, and Sherlock continued his work. Unfortunately, John was not easily deterred. He lay a hand on Sherlock’s arm. “Answer Mary's question.”

“She already knows the answer. Any conversation would be a waste of time.”

“She's being polite, as you should be,” he said, his grip on Sherlock's arm tightening.

Mary settled into Sherlock's armchair with a book. “It's all right, John. I'll just read.”

“No, go back to the kitchen!” Sherlock shouted at her.

“That is quite enough of that,” John said, rising and pulling Sherlock to his knees, then staring sternly down on him when Sherlock refused to stand. “If you insist on being rude, you can sit on the staircase where it's not going to bother anyone else.”

“No, you didn't give me my warning!” Sherlock scrambled back onto his bum and slid as far as possible from John's forbidding face. “You have to give me an opportunity to manage my own behaviour before you intervene.”

“You've had plenty of opportunities tonight, and you've chosen to be extremely naughty.”

“But you didn't give me my warning,” he cried, and he wasn't faking when tears filled his eyes at John's betrayal of Sherlock in favour of Mary.

John sighed, and Sherlock wondered whether he'd be called on the fact that he doesn't always get a warning, especially not for egregious rudeness. “Consider yourself warned,” John said. “You know how to behave, and if you can't manage it on your own, you'll be sitting on the stairs outside the flat until you can.”

Sherlock wiped the tears from his eyes and tried to ignore Mary's presence in his chair and his life.

* * *

Sherlock leaned his head on John's shoulder as they cuddled together in bed. The story of Benjamin Bunny lay on Daddy's lap, and he thought about how he was lucky he had John as his daddy and not Mr. Bunny.

“Benjamin Bunny's daddy is mean.”

John smiled and cuddled him tighter. “Benjamin and Peter did something extremely dangerous. I'm sure he was very concerned for their safety.” He slid from under the blankets, then straightened them back again. “Let's get you tucked up and snug.”

Sherlock squirmed down until John could tuck him up properly. “Yeah, but Peter's mummy was concerned, too, and she didn't whip him, even when he lost his shoes and coat. She's nice, like you.”

“This book was written a long time ago. Back then, people thought of dads more as stern disciplinarians, while mums just took care of you.”

Sherlock thought that through as John sat on the edge of his bed and ran kind fingers through his hair. “I'm glad you're not mean. You're more like a mum than a dad. That's why I don't want mummy, because I already have you for that.”

John's face scrunched up. “Let's think of me as a modern dad.”

Sherlock was fine with that, as long as it didn't leave any room for someone else to weasel into their family. “Still, I don't want a mummy. I only want you to take care of me.”

“You have Mrs. Hudson. She takes care of you.”

“Yeah, but she's not my mum.”

“She's not,” John agreed. “And even if she and I got married, that wouldn't make her your mum. That would be between you and her.”

Sherlock pondered that as John leaned down to kiss his forehead.

“I love you, Sherlock, and I'm not the only one.”

* * *

Sherlock stood in John's bedroom doorway for several minutes, staring at John and Mary. She was curled toward him, and he slept on his back. He wondered whether it meant anything, then grudgingly admitted to himself that it was unlikely. At last, John stirred.

“What are you doing out of bed?”

“I'm not sleepy. I want to cuddle with you.”

John pushed himself to a sitting position, a low groan accompanying the effort. “Let me take you back down to bed.”

“No, I want to cuddle in your bed. Mary can go back to her flat.”

“Sherlock,” John warned. “You're being rude.”

Mary propped herself up on her elbows. “It's all right, John. There's enough room for three people.”

Baulking at the idea of sleeping next to Mary, Sherlock stomped his foot. “No there's not. You have to go back to your flat.”

The outburst was enough to pull John from bed and Sherlock was torn between throwing himself into his daddy's arms and shrinking back from him. “Mary and I are engaged, and that means we sleep in the same bed. If she were to go back to our flat, then I'd have to go with her, and neither of us are willing to leave you alone.” He put a soft hand on Sherlock's cheek. “Now, do you want me to take you back to your bed, or would you rather stay here with us?”

Trapped by John's words, Sherlock did the only thing he could do. He stomped over to the bed and threw himself under the blanket, then jerked it to his chin and glared at John. John followed at a more measured pace, and Sherlock scooted back from him as he lay down. In fact, Sherlock scooted so far back that he pressed into Mary, running the risk of pushing her off the bed entirely. The thought cheered him a bit, until Mary's arm wrapped gently around him.

“I enjoyed spending time with you today,” she whispered. “I never knew half that about pollen.”

Of course she hadn't. She was a nurse, and not a very good one judging by the wear pattern on her shoes. Sherlock squirmed in her embrace and stretched out his legs, shoving her feet off her side of the bed. Unfortunately, John saw what he'd done and frowned. Curling up to allow Mary her space, Sherlock hid his face in the mattress, until he felt John's hand on his shoulder.

“Come cuddle with Daddy, love,” John said, and Sherlock crawled over to fall into his waiting arms. “That's my good boy.”

Letting the words sink in, Sherlock sniffled a bit. He'd been anything but good all day. He'd been rude and insulting, had refused his dinner, had stropped at bedtime, and had generally done everything possible to ensure that Mary had such an unpleasant time that she'd never want to return. He'd done all that and still John seemed to think that he was good. Moreover, John was stroking his hair and kissing his temple and telling Sherlock that he loved him.

It was more than Sherlock could handle, having everything that he wanted and knowing that he would lose it all again when John left. He began to sob, and John held him tighter, lifting him until they were both propped up against the pillows.

“What's the matter, love?” he asked, and Sherlock just shook his head into the crook of John's neck. The mattress shifted as Mary rose from the bed. When Sherlock heard her leave the room, it didn't feel like a victory. Nothing seemed to matter as he sobbed out his fears and despair into the collar of John's shirt.

When he finally looked back up, Mary was back, handing a glass of water out to John, who took it and held it to Sherlock's lips. “Take a few sips,” he said, and Sherlock obeyed.

“Do you want some paracetamol?” Mary asked him, and he nodded, too exhausted to maintain the emotional embargo he'd put in place. She handed him the tablets, chewable ones that tasted of artificial cherry flavouring and sugar substitutes. He wrinkled his nose and drank down the rest of the water, his eyelids already heavy from the excess emotion.

John took the glass from him and set it aside, then kissed his cheek. “Lie down and I'll rub your back.”

Sherlock lay on his stomach and let John run a hand up and down his back. He didn't even mind when Mary lay down beside him and wished him a good night. Their fingers brushed each other as she made herself comfortable, and Sherlock let it happen.


	2. Chapter 2

In the morning, Sherlock found himself under Mary's arm again. He wondered at the soft weight of it, both similar and different to the feel of John's. He wriggled slowly toward her, cataloguing the warmth of her skin through their pyjamas, the hiss of her breath in his ear, and the tickle of her hair on the side of his face.

“Good morning,” she murmured, and he rushed back to the safety of John's body. 

John startled awake at the sudden movement. “What happened?” he asked, as Sherlock clung to him.

“Nothing. I just want to hug you.”

John checked the time, then groaned. “Let's sleep a little longer.”

“Mary woke me up.”

Mary didn't deny it, just stood and rubbed at John's legs through the blanket. “You two have a lie-in. I'm going to get something from the shop and make a nice breakfast.”

Sherlock barely noticed her departure as he fell back into sleep, comforted by the feel of John's arms around him. They both dozed for a bit, until the smell of eggs and sausages woke them again.

“Smells like Mary made us a fry-up,” John said.

The stumbled downstairs, where the food was already on the table. John kissed Mary good morning, and Sherlock decided he wasn't hungry.

“Just a few bites, love,” John said, and Sherlock pushed their chairs together, so he could lean up against him. John rubbed his back. “You're so little. Do you want me to feed you?”

Too little and too sleepy to answer with words, Sherlock nodded, and John put some eggs on a fork and brought it to Sherlock's lips. Sherlock shook his head. “Sausage, Daddy,” he said, but John used the opportunity to put the fork full of eggs into his mouth. Sherlock swallowed, and John ensured the next bite had sausage as well as egg, getting a kiss from Sherlock for his efforts. Mary smiled at their interaction, and Sherlock hid his face in Daddy's shoulder. “Toast, Daddy.”

“Just a few more bites of egg and sausage, and you'll get toast,” Daddy promised.

Sherlock ate the requisite egg and sausage, and Daddy fed him the promised toast, placed upside down in his mouth so the strawberry jam exploded with sweetness on his tongue. Sherlock kissed him again, then hugged him tightly.

“We can cuddle, but you have to let Daddy eat,” Daddy said, and Sherlock nodded his assent.

John ate with his left hand, while his right continued to cuddle Sherlock, rubbing at his back and neck, then running fingers through his hair. Mary and Daddy talked, but Sherlock ignored their conversation until their plates were all empty and John spoke. “Will you help Daddy with the washing up?”

Sherlock nodded, and Daddy rewarded him with a warm smile. “That's my good boy.”

Sherlock poured the fairy soap into the sink and watched it fill with soapy water, splashing his hands until bubbles floated into the air. John washed each dish, and Sherlock inspected them and placed them carefully on the rack. Then John took a damp tea towel to Sherlock, wiping any and all traces of breakfast from his face and hands.

“I think we can put off washing your hair until tomorrow, but you need to brush your teeth.”

“You, too, Daddy.”

They brushed their teeth together, then joined Mary in the sitting room, where Sherlock immediately rearranged the sofa cushions to make a fort for himself. He sat inside it, observing Mary and John and making his deductions.

Mary was always the first to laugh.

John sneaked glances at her when he thought she wasn't looking.

She wasn't looking, but she noticed.

Sherlock frowned. She noticed John, and she noticed Sherlock, but she wasn't looking at either one. She wasn't concerned with John's attention, because she knew the influence she had on him. She wasn't concerned with Sherlock's attention, because she knew that he wasn't a threat to her relationship with John. It explained why, unlike John's previous girlfriends, she could brush off Sherlock's rudeness. All she needed to do to end it was to tell John to leave Sherlock. She was just toying with him, like a cat batting around a mouse fighting for its survival.

Sherlock kicked through the cushion fort he'd made and stomped over the coffee table toward his room.

“Oy! You know better than to walk on the furniture,” John said to him, but he ignored the reprimand and stomped even harder. “Sherlock, come back here and tidy up the sofa.”

By the time John had spoken, though, Sherlock was already to his room. He slammed the door on John's command and threw himself onto his bed.

“What in the world was that?”

Sherlock had been so immersed in his misery that he hadn't noticed John's entrance. In lieu of answering, he pounded his fists and feet on the mattress.

John sat down beside him. “If you feel like you have to hit something, the mattress is a good choice. Let me know when you're ready for a hug.”

Scrambling to his knees, Sherlock hugged John, and was hugged in return. “That was a brilliant way to work through a strop,” John praised him, and Sherlock smiled slightly, then even more when John pulled back to kiss at his face. “Can we go back out and tidy up the sofa now?” 

Sherlock shook his head. “I don't want to go back out there. I hate Mary.”

Closing his eyes, John took a deep breath, and Sherlock bit his lip at the unspoken rebuke. “You don't have to love her, but she loves you, and she loves the fact that you and I love each other.”

Sherlock squirmed at the uncomfortable thought of everyone loving each other but him.

“And whether you love her or not, you have to be polite, and treat her with the same respect I expect you to treat anyone else with.”

Sherlock glowered, but John ignored it and led him back out to the sitting room, where Mary was already setting the sofa to rights. Suddenly furious, Sherlock ran to her and snatched the cushion from her hands. “Stop messing up all of my things!”

Startled by his reaction, Mary stepped back.

“Sherlock Holmes, she was trying to help you.”

Clutching the pillow to himself, Sherlock faced John. “You told me to tidy up the sofa, and then she was doing it before I had a chance. I was only doing as you asked, and she was trying to stop me. You can't be angry at me for trying to do as you asked.”

Unimpressed with his logic, John took the cushion from him and set it back on the sofa. “Sherlock, you are one of the cleverest people I've met, and you know exactly how you are to behave.”

When John put it like that, it was hard to deny.

“Now, you owe Mary an apology.”

Impotent rage filled Sherlock's chest. “No! She's messing everything up!”

“John, that's really not necessary,” Mary said, but John held up a silencing hand, and she turned away, pinching the bridge of her nose.

“Sherlock, this is your last warning.”

Standing his ground, even in defeat, Sherlock shook his head and began to cry. John led him out the door and sat him down on the stairs. “I'll be back in five minutes.”

Sherlock closed his eyes and leaned against the wall. He was wallowing in self pity when he heard Mary's voice from the flat.

“I wish you hadn't done that.”

Sherlock sat up and listened for John's response. “I won't allow him to treat you that way.”

“I can handle it.”

“This isn't about what you can or can't handle, Mary. It's about Sherlock and his choice to behave reprehensibly today.” There was a lull, and Sherlock wondered whether they knew he was listening, until John finally asked, “What's that look for?”

“I've never seen this side of you before.”

“What side is that?”

“The father side, being a good dad, prioritising your child. It makes me think this might work.”

Sherlock leaned in, but the conversation was over. He heard them making tea, and he wondered what Mary had meant, how John being a good caregiver would make any particular thing work. He briefly considered that Mary might be pregnant, but she hadn't exhibited any other signs, and it didn't make sense that she would use John's relationship with Sherlock as a testing ground for his fitness for parenthood.

John's return interrupted his musings. “How are you feeling?”

Sherlock nodded, an ambiguous response, but enough for John to crouch down to hug him.

“Are you ready to apologise to Mary, now?”

Sherlock shook his head into John's neck, and John leaned back.

“Sherlock, you were very rude to Mary earlier, weren't you?”

Sherlock nodded, knowing where this was going, but unable to get there himself.

“And when we're rude to people, we apologise afterwards, don't we?”

He nodded again.

“So can you show me how you're my good boy and apologise to Mary?”

Reluctantly, Sherlock nodded his head, and John hugged him again, calling Mary over. When she arrived, John prompted, “What did you want to say, Sherlock?”

“Sorry,” he mumbled, straight into John's jumper. It was a terrible apology. He hadn't looked her in the eye, or really seemed sincere at all, but before John had a chance to demand a better one, Mary had already accepted it.

“That's okay, sweetie. I know this is a tough adjustment.”

Sherlock ignored her and held on to his John.

* * *

John closed the story book and swung his legs to the floor. “All right, love, time for sleep.”

“I'm not sleepy,” Sherlock protested. “And I want another story.”

“You've already had two. Now it's time for sleep.” John leaned down to kiss him, and Sherlock used his trump card.

“But I want Mary to read me a story.”

John stared at him, measuring, and Sherlock knew that his ploy was transparent. Still, he had faith that it would be effective, especially with John's desperate need for Sherlock and Mary to form some sort of relationship. “Please?” he asked.

John compressed his lips, but nodded. “Okay, I'll get her.”

Soon, Sherlock was choosing his third bedtime story, an unprecedented victory. He was determined to enjoy it, even at the cost of sharing it with Mary, who sat on the bed beside him.

“The sun did not shine. It was too wet to play,” she started, and Sherlock couldn't refrain from joining her on the next two lines. “So we sat in the house all that cold, cold, wet day.”

Voice suitably lively as the cat, and uptight as the fish, Mary continued, and Sherlock found himself falling into the story, leaning in for a better view of the illustrations, which she graciously turned for him to see.

“What would you do, if your mother asked you?” she concluded, closing the book and smiling at him.

“I don't have a mother. I don't want one,” he told her.

“Ah, then what would you do if John asked you?”

“It's a ridiculous question. The entire scenario hinges on the fantastical premise of a magical anthropomorphic cat.”

“I see,” she said, setting the book aside. “And does this aversion to ridiculousness mean that you don't want another story?”

“No, you have to read _Green Eggs and Ham_!”

“Of course,” she replied, untroubled by his outburst. She opened the book and he crowded in to see the illustrations.

“I am Sam,” she began, and he followed along, chiming in when he could, sometimes before she read the lines herself. They proceeded through the pages together, and at the end, when the reluctant protagonist finally acquiesced and thanked Sam, Sherlock found himself leaning up against Mary's shoulder. He quickly righted himself.

“I guess he just needed to give something new a chance,” Mary commented.

Sherlock chewed on the inside of his lip. “In an imaginary world where a car can drive up a tree, anything can happen.”

“Quite so. The possibilities are endless.” She stood and straightened the blankets around him. “May I kiss you goodnight?”

“Only on my hair. Not on my skin,” he allowed.

She complied, and walked to the doorway, where she turned off the overhead light. “Good night, Sherlock.”


	3. Chapter 3

Sherlock sat reading in his sofa fort, shielded from Mary's presence at the table, as John packed their bags upstairs. One of John's jumpers was currently wrapped around Sherlock's feet, keeping them warm. He hoped John wouldn't miss it.

“I'm going to make some tea. Would you like some, Sherlock?” Mary asked.

Sherlock ignored her in favour of wriggling his toes in the scratchy wool of the jumper. In fact, he did want tea, but not from Mary. Perhaps Mrs. Hudson would bring him some after John and Mary left. The thought wasn't as appealing as it should be.

Mary's head appeared between the cushions. “Did you hear me, Sherlock?” she asked, kind as ever.

Sherlock, however, refused to fall victim to her warmth. He turned from her and reminded himself that she'd be gone within a few hours. 

“You work so hard to dislike me,” she said, and when he didn't reply, continued blithely on. “But you know, John loves you so much, and I love John so much, that it would be difficult for me not to love you.”

“I suppose if John loved you more, I'd be forced to love you, too.”

“Sometimes, my dear, you are too clever for your own good,” she laughed, running her fingers through his hair.

If felt good, and Sherlock came to the horrifying realisation that he did, in fact, love her. Maybe not in the same way that he loved John, but enough to want to crawl into her arms and be forgiven for treating her so horribly over the past two days. Even worse, he knew that she was perfect for John.

Sherlock didn't cry.

“Mary, have you seen my beige jumper?” John's voice called from the stairwell.

“Not since you wore it.”

“Well, it didn't very well sprout legs and walk away, did it?”

“I'll be right back,” Mary told him, then left the room.

Sherlock poked his head out of his fort. He considered secreting the jumper away somewhere, but in the end, he knew he didn't really want it. He wanted John. He wanted John, and John wanted to pack his bags and leave. John wanted to leave with Mary back to the flat they shared together, the life they shared together without Sherlock.

It was too much. He didn't want to watch John leave, and definitely not with Mary. The open flat door caught his eye, and he suddenly realised that he didn't have to watch them leave at all.

* * *

After thirty minutes on the streets of London, Sherlock was beginning to regret his decision to leave his coat and scarf behind. While it had certainly afforded him a longer lead time in which John and Mary didn't know he was missing, the cold was beginning to seep into his bones. He wrapped John's jumper around his trembling fingers and sternly told himself to ignore his transport's plea for warmth.

After an hour, he thought some tea might be nice. He belatedly remembered that his wallet was in his coat pocket, where he'd be sure not to forget it when rushing out for a case.

After an hour and a half, he noticed the CCTV cameras tracking him. 

“Mycroft,” he muttered, then flung a choice gesture at the nearest camera. Of course John had called Mycroft when Sherlock went missing. Resisting the bubble of delight that John was searching for him, Sherlock ducked into the nearest dead zone.

It wasn't too difficult to avoid the cameras, and Sherlock made good time, buoyed by the fact that he was being pursued. Around corners, behind lorries, and under awnings he went, until he reached his destination: a deserted alley completely devoid of cameras, with a sturdy access ladder to the roof. He was rubbing enough warmth back into his fingers to grab the rungs when Mary Morstan appeared in the entryway.

“Sherlock, thank God!” She wrapped her arms around him before he could flee. “You're freezing! What in world made you think it was a good idea to traipse around London in the dead of winter without a coat?”

Clearly the question was rhetorical, and Sherlock ignored it, just as he ignored the tight grip she kept on his elbow as she phoned John with her other hand. He wasn't sure whether he wanted to get away.

“I found him.” She scanned the alley. “Just luck, I guess. We'll meet you back at the flat.”

As she put the phone back in her pocket, Sherlock shook away from her grip. “There's really no need to accompany me, Mary. Mrs. Hudson will let me in whenever I decide to return.”

“Are you joking?” Another rhetorical question, intended to convey her outrage. “John's been out of his mind with worry about you, as have I for that matter. You don't have your coat. You don't have your phone. No keys. No money. No identification.”

As she ticked off all the provisions Sherlock lacked, he rolled his eyes. “And yet I've managed to survive a full two hours.”

“Don't you dare get smart with me. I've spent those two hours terrified of what might happen to you.”

“Please, Mary.” Sherlock's voice practically dripped with disinterested condescension. “You and I have no relationship outside of our mutual connection to John.”

Mary stepped back, but only for a moment. She then pulled herself up until she almost seemed to tower over him, and pointed right at his face. “Stop it. Stop pretending that you don't know how much I care about you.”

“Frankly Mary, it's irrelevant.” It was a bit of a struggle to maintain the patronising air, but Sherlock had practise. “I suggest you go back to John, and-”

“Sherlock, you are not nearly as good a liar as you think you are, and I'm not going to allow you to play the game where you push us away and pretend not to have human emotions.”

“Allow me?” he scoffed.

“Yes, allow you. I have been very indulgent of your atrocious behaviour all weekend because I know you're dealing with a difficult situation, but you've now worked yourself into such a state that you're putting yourself in danger. John is not leaving, and I'm not leaving, but if you continue this, big or little, I will smack you.”

Sherlock peered down at her with all the condescending scepticism he could muster. “No, you won't. You-”

The smack took him by surprise, stinging through the seat of his trousers and making him again wish that he'd worn his coat. The stinging of his eyes soon overshadowed it, though, and he felt himself falling further and further into his little self. He sneaked a watery peek at Mary, who wasn't gloating at all. She just looked tired, worried, and maybe a little sad. Letting the tears flow freely, he leaned slightly into her, and she quickly took him into her arms.

“I know, I know,” she soothed.

“I don't want...” he started, then lost track of the thought.

“I know, sweetie. It'll be okay.”

He believed her.

* * *

John wasn't home when Sherlock and Mary returned. Sherlock hadn't expected it, either, not after a car had arrived to whisk Mary and him back to the flat. Sherlock had ignored Mycroft's meddling and instead focussed on Mary, who rubbed warmth back into his fingers, then quickly sent him to bed with a promise of tea. He hoped it would be camomile, just as Peter Rabbit's mum had made when he'd gone on his adventure in Mr. McGregor's garden.

By the time Mary came in with the tea, Sherlock was in his pyjamas under the blanket. She sat down next to him and handed him the warm mug, then used her newly unoccupied hands to straighten the blankets around his legs. Sherlock tucked himself into her as he sipped the warm tea and let her run her fingers through his hair.

“Are you feeling better?” she asked, and he nodded. The tea wasn't camomile, but it was soothing, and not too hot at all. Moreover, he was certain that he wasn't in trouble with her, though he couldn't say the same for his status with John, who would most certainly categorise Sherlock's most recent behaviour as a 'safety' issue.

As if summoned by Sherlock's thoughts, John's footsteps sounded on the stairs. Soon the man himself rushed into the bedroom, still in his winter coat.

“Are you all right?” John asked, rushing over to inspect Sherlock himself without waiting for an answer. “Mary, how did you find him?”

Mary shrugged. “Just luck, I guess.”

Ignoring the implausibility of the response, John ran his hands over Sherlock's arms. “What were you thinking?!” 

Before Sherlock could say anything, John shook his head sharply. “Never mind. That was incredibly dangerous. Anything could have happened to you out there.”

“But I was big,” Sherlock protested.

John's eyebrows rose. “You were big when you left behind your phone, your coat, and your wallet?”

Sherlock held his tongue, reluctant to push John further into anger. Mary's hand still rested on his back, and Sherlock curled into her as John ran a frustrated hand over his face.

“Mary, I need to talk to Sherlock alone for a bit.”

Mary extricated herself from the cuddle and stood. “Can I see you first?”

They entered the kitchen, leaving Sherlock to nurse his tea alone. He sipped it carefully and listened as best he could do. It didn't take long for John's voice to boom out clearly.

“You did _what_?!”

Try as he might, Sherlock couldn't hear any more of the conversation, though it was clear that John was unhappy with something Mary had done, presumably smacking Sherlock. The thought didn't warm him as much as he thought it would. He set his empty mug down on the floor and crept to the door. He could barely hear Mary's whisper.

“-isn't working, John. You have to talk to him, now.”

“We agreed we'd try visits for a few weeks before we made a final decision.”

“That was before we knew how difficult the back and forth would be on him. It's just prolonging the inevitable, and we're all suffering in the process.”

“Fine, next week-”

“Now, John.”

John didn't reply,other than walking toward Sherlock's bedroom, and Sherlock scurried back to the bed, his mind reeling from what he had just overheard. He didn't want to know anything John had to say to him, and he pulled his blanket over his head.

“Sherlock, sit up and look at me.” Sherlock continued to hide until John sharply commanded him, “Take the blanket off your head and sit up.”

He unwillingly obeyed, and immediately regretted it as he saw John's grim face directly above him.

“Sherlock, you are not to leave the flat without permission. If you want to go somewhere, you ask. You do not leave on your own, and you certainly don't storm off because you're cross. The only reason you're not getting smacked right now is because I believe you that you were aged up a _bit_ when you left.”

Sherlock hadn't anticipated that John might smack him, and he hugged his pillow at the prospect. That he would end their relationship by smacking Sherlock and leaving was unthinkable. He tried to turn his despair into anger at Mary, but it was impossible. Furthermore, he was certain that Mary smacking him had factored into John's decision not to do so himself.

“You are grounded for the week, however. That means no leaving the flat, no laptop, no phone, and no telly.” 

Sherlock pondered the implications of the punishment. None of those things would affect him as young as his headspace was, though he'd probably feel their absence keenly if he were to age up even a bit. He could stay little for the duration of the week and avoid punishment entirely, which may have been John's intention all along. The larger question, of course, was how John planned to enforce his directive from his own flat. Sherlock considered and discarded several possibilities, none of which seemed feasible. Perhaps this was John's form of final mercy, a punishment that he wouldn't enforce, but John had always been adamant about following through on everything. Sherlock hid his face behind the pillow as he continued to sift through and weigh the probabilities of various scenarios.

John's voice was gentler as he sat on the bed opposite Sherlock and pulled the pillow from between them, “I know you don't-”

Like a protein folding in on itself, the information that had lay formless in Sherlock's mind suddenly collapsed into a firm structure, supported by everything he'd observed, and the answer was clear to him. He jumped from the bed and ran to the kitchen, where Mary sat sipping her tea.

Heedless of the mug, and of the hot liquid that splashed over him, Sherlock threw his arms around her. “You brought him back.”

“I told him he was grounded and he ran off.” John was right behind him, stern and somewhat bewildered.

“You can't be grounded unless Daddy's here, can you?” Mary asked, petting Sherlock's hair as she dabbed tea from both their trousers.

Sherlock shook his head. “You said you'd talk him round, and you did.” 

Then Daddy was hugging him, too, and everything was perfect.


	4. Chapter 4

“No, Daddy. I want you to stay here with me and Mary.”

“Sorry, love, but Daddy's already taken far too many days off to solve cases with you. Now, can you behave for Mary, or do you need to age up?”

Sherlock certainly didn't want to age up, not when he was still grounded from everything that made being older interesting. Even if he were in his adult headspace, he thought the grounding might still be in effect. He wasn't sure how John could enforce the edict, but as both John and Mary seemed more indulgent the smaller Sherlock was, it didn't seem worth the risk.

“I want to be little.”

“All right. Do not open the cupboard with your phone and laptop, and the telly stays off.”

“But what if Mary wants to watch it?”

“Then Mary may turn it on, but I don't want to hear any reports of, 'Daddy said I could watch telly with you.' Daddy did not say that. Daddy said Mary could watch telly and you could be in the room with your eyes open.”

Sherlock pouted at the double unfairness of being scolded for something he hadn't done and for having his plans routed before they were put into action.

“John, you'll be late.” Mary approached them, John's coat in hand. They kissed, and Sherlock wrinkled his nose at it.

John kissed Sherlock as well, pulling him in for one last hug before setting out the door.

“No telly!”

* * *

Sherlock leant on Mary's shoulder, watching the programme that he'd chosen for the both of them. Mary didn't seem to mind, and he shifted around until his head was in her lap and she began to stroke his shoulders and back. He drifted in and out, until the programme was finished and Mary turned off the telly. He turned on his back and yawned.

“Mary,” he asked, “what if you were my mum?”

His eyes were closed, but he felt her gaze, and then her hand on his face. “Well, I suppose I could cuddle you as much as I wanted. And kiss you on your skin, not just your hair.”

Sherlock pondered the answer. He didn't think he'd mind Mary kissing him on his skin, though he enjoyed having the power to deny her, at least temporarily. He peeked up at her.

“Would you set me on the naughty step, though?”

“If you were persistently naughty, I imagine I would,” she answered. “But I'd do that anyway, mum or not.”

Brow furrowed, Sherlock chewed his lip. “Would you smack me?”

“I don't imagine it would come to that, now that you trust me enough to listen.”

She was probably right, but Sherlock was unwilling to admit it. He wasn't sure how he felt about her confidence in predicting his behaviour, even if it was well-placed.

“Sherlock, I really don't think it would change much of anything. Even if I'm not your mum, I still want to take care of you.”

He sighed. He didn't mind her taking care of him so much as he minded that he was no longer the singular focus of John's attention.

“Sherlock, are you thinking of drafting a contract between us?”

Sherlock shook his head. “I'm collecting data.”

“Ah. May I propose an experiment, then?” she asked, and he turned his curiosity toward her. “What if we were to pretend that I'm your mum for the next few hours?”

* * *

The experiment was quite the success, though it certainly didn't conform to a strict interpretation of the scientific method. Still, Sherlock was able to collect quite a bit of data on Mary and the effect that motherhood, even of the unconventional sort, may have on her.

The most obviously difference was her current unwillingness to tolerate poor behaviour.

“Sherlock, is that any way to talk to your mum?” Mary's voice and eyes were amused, even in the midst of the rebuke. Her amusement in the face of Sherlock's rudeness lay in sharp contrast to John, who was always displeased by misbehaviour.

Several responses crossed his mind. While he could feign ignorance of the social lines that he'd crossed, Mary had proved herself to be even more adept than John at detecting Sherlock's deception, and deception most certainly did _not_ amuse her. “No,” he finally conceded.

“No, it's not,” she agreed, kissing him on the forehead. “May I have an apology, then?”

There was never a question of his compliance. She regarded him with such affection and expectation, that he fell readily into his role. “Sorry, mummy.”

“That's better, isn't it?” She ran her fingers through is hair and kissed him again, this time on the the cheek.

Therein lay the second difference since the experiment had begun. Mary could barely get within a metre of him without squeezing his shoulder, kissing his temple, petting his hair, or engaging in some other form of physical affection.

The third difference was her insistence on engaging Sherlock in her own activities. In the past few hours, he had gone to Tesco, baked treacle cookies, and even helped Mary to evaluate venues for the wedding.

All in all, the experience hadn't been entirely horrible, just markedly different to spending the day with John, as was carefully documented in Sherlock's mind palace. He was in the midst of cataloguing Mary's latest round of affection when he heard the sound of John's arrival downstairs.

“Daddy!” he shouted, and jumped from his specimens to meet Daddy at the bottom of the stairs.

“Hello, love.” Daddy kissed him on the cheek, and Sherlock held tightly to him, determined to keep him as close as possible after an entire day apart. Devoid of all but the most rudimentary deductive powers, John was completely ignorant of Sherlock's activities for the day, and Sherlock was keen to fill him in on every detail.

“Mummy and I made cookies!”

“You and Mummy, hm?” John put an arm around Sherlock, and they began to ascend the stairs.

“Yes, and I chose where you're to be married!”

Sherlock had deduced that Mary's first choice would be next to a demolition site at the time of the wedding, and the second was at a high risk of rat infestation.

“It sounds like the two of you had quite the day, you did.”

They arrived at the flat door, where John kissed Mary. Sherlock didn't even mind, at least not until John greeted her with a self-satisfied smile: “Hello, Mummy.”

“No, Daddy! Mary's _my_ mummy!” Sherlock wriggled his way between them and clung to her as evidence. “She can only be your fiancée and then your wife.”

Sherlock prepared himself for the inevitable comment on his rudeness, but Mary only hugged him back as John smiled at them both.

* * *

“But I want Mary to read me a story, too,” Sherlock pleaded.

John tucked the blankets around him and kissed his forehead. “Sorry, love, but Mary's already asleep.”

Mary had said she was completely knackered not long after dinner. John seemed to think it was because of Sherlock, even though Sherlock had been assisting with all her tasks the entire day, assistance that she would not have gotten had she gone to work.

“I think I'll be big again tomorrow,” Sherlock said.

John turned around from where he was replacing _Green Eggs and Ham_ on the shelf. “If that's what you want.”

“And you won't leave? Even if I'm big?”

“We'll go to work, but we'll come back.”

John's reassurances relaxed him, and his eyelids drooped heavily. “You'll always come back to me, right?” he murmured.

“Always.”

“Because we're best friends.”

“We are,” John smoothed a hand over Sherlock's hair. “And I would love you in a boat, and I would love you with goat. And I will love you in the rain, and in the dark, and on a train. And in a car, and in a tree. You are so good, so good, you see.”

The words washed over him, familiar and true. “I love you, too, John.”

“Good night, love.” John's voice began to fade as Sherlock drifted into darkness. “I'll see you in the morning.”

“And every morning,” Sherlock added.

“And every morning.”


End file.
